Largest Study Of Urban Wildlife

photo from Daily Herald

article written by Russell Lissau, Daily Herald Staff

The squirrels that eat the seed out of your bird feeder, the raccoons that tear up your trash and the coyotes that occasionally hunt pets in your neighborhood are driven by the same natural instincts and environmental pressures.  As man has developed what were once pristine natural habitats, these often-pesky mammals have been forced to scrounge for food wherever they can find it - including our backyards.  This week, urban wildlife ecologists from Chicago's Lincoln Park Zoo will team with the Lake County Forest Preserve District and other agencies to begin a study of area mammals.  Using video surveillance, the scientists will try to identify significant populations of medium- and large-sized mammals in Cook, Lake, DuPage and Will counties.  Two Lake County forest district sites have been confirmed for the study. Sites in the other counties are not being revealed, organizers said.  Wildlife experts hope to use the results to minimize conflicts between people and their four-legged neighbors.  "It's going to be the most thorough study of urban wildlife that's ever been completed," said Seth Magle, an urban wildlife ecologist with the zoo.  Scientists with the zoo's Urban Wildlife Institute will lead the study, which is scheduled to last at least five years. They'll be looking for raccoons, foxes, coyotes, skunks, deer, opossums and other mammals throughout northeastern Illinois.  The target area is a semicircle that starts in Chicago's Loop and stretches west, north and south for about 31 miles. More than 100 sites have been selected for the start of the project.  "Our goal is to capture the full range of urbanization," Magle said.  Two Lake County forest preserves - MacArthur Woods near Libertyville and the Ryerson Conservation Area near Deerfield - are among the sites to be studied.  The ecologists will conduct video surveillance for four weeks in each of the four seasons. One camera will be placed at each site.  The waterproof and tamper-resistant digital cameras will be equipped with infrared triggers and flashes that will minimize their visibility. Baits such as fatty acid scent tablets will be placed near motion sensors and will attract animals already in the area.  The baits are not strong enough to artificially increase animal populations, officials said.  The scientists will use the video images to compare the densities of various animal populations, said Gary Glowacki, a wildlife biologist with the Lake County forest district. A mammalian census is not part of the plan.  "We're not counting every single animal," Glowacki said.  The animals will only be filmed the first year. In future years, scientists could use live trapping to place monitors on the animals and test their genes, Magle said.  "We're trying to be as noninvasive toward the animals as we can," he said of the initial work. "And cameras are as noninvasive as it gets."  The ecologists are particularly interested in preventing the spread of animal-related illnesses, such as rabies or roundworm, cases of which can increase when mammalian populations grow, Glowacki said.  Expanding predator populations can also negatively affect the viability of smaller species, such as turtles that lose their eggs to raccoons or other mammalian hunters, he said.  "It throws the whole ecosystem out of balance," Glowacki said.  The scientists hope the research leads to new wildlife management strategies and techniques.   For example, open space at a local forest preserve could be expanded to eliminate the natural cover some predatory animals use when they're on the move, Glowacki said. That would make the area less hospitable for the creatures without taking more drastic steps like trapping or hunting.  "As wildlife biologists, our goal is to manage populations of wildlife the best we can," he said. "We're not going to completely remove man's influence on the landscape, but there are things we can modify to keep it in check in the least invasive way."